Tax Penalty Calculators
Work out estimated IRS penalties and interest before you file. These calculators model the federal underpayment and failure-to-pay rules so you can see roughly what you may owe and plan ahead.
- IRS Underpayment Penalty Calculator Estimate the Form 2210 penalty for underpaying estimated tax, including safe-harbor checks.
- Late Tax Payment Penalty Calculator Estimate IRS failure-to-file, failure-to-pay penalties and interest on a late tax balance.
These calculators are free, require no sign-up, and run entirely in your browser. Each one shows a full breakdown of how the result is reached, with worked examples and answers to common questions. Looking for something else? Browse all calculators.